At 294 KB, this PDF is larger than its neighbours but still identified only by 2SJ167, a Japanese JIS number for a P-channel field-effect transistor. It is filed as a schematic, yet a part-number name like this normally points to a manufacturer datasheet, possibly with extra characteristic curves. Repairers consult it for pin assignment, maximum ratings and switching behaviour when diagnosing a shorted or open device. Open it in any PDF viewer, and verify that any replacement shares the same channel type, package and pinout.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @cyberlanelectonik. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.